Traditional Local Area Networks (LANs) exchange data using Ethernet, a frame-based standard that allows high-speed transmission of data over a physical line. Since its initial implementation, the Ethernet standard has rapidly evolved and currently accommodates in excess of 10 Gigabits/second. Furthermore, because Ethernet is widely used, the hardware necessary to implement Ethernet data transfers has significantly reduced in price, making Ethernet a preferred standard for implementation of enterprise-level networks.
Given these benefits, telecommunications service providers have sought to expand the use of Ethernet into larger-scale networks, often referred to as Metropolitan Area Networks (MANs) or Wide Area Networks (WANs). By implementing so-called Carrier Ethernet, service providers may significantly increase the capacity of their networks at a minimal cost. This increase in capacity, in turn, enables provider networks to accommodate the large volume of traffic necessary for next-generation applications, such as Voice over Internet Protocol (VoIP), IP Television (IPTV), and Video On Demand (VoD).
Because Ethernet evolved in the context of local area networks, however, native Ethernet has a number of limitations when applied to larger scale networks. One key deficiency is the lack of native support for Operation and Maintenance (OAM) functionality. More specifically, because network operators can typically diagnose problems in a LAN on-site, the Ethernet standard lacks support for remote monitoring of connections and performance. Without support for such remote monitoring, network operators of large-scale networks would find it difficult, if not impossible, to reliably maintain their networks.
To address the lack of native Connectivity Fault Management in the Ethernet standard, several organizations have developed additional standards describing this functionality. In particular, the International Telecommunication Union (ITU) has published Y.1731, entitled, “OAM Functions and Mechanisms For Ethernet-Based Networks,” the entire contents of which are hereby incorporated by reference. Similarly, the Institute of Electrical and Electronics Engineers (IEEE) has published 802.1ag, entitled “Connectivity Fault Management,” the entire contents of which are hereby incorporated by reference.
Y.1731 and 802.1ag describe a number of mechanisms used to detect, isolate, and remedy defects in Ethernet networks. For example, these standards describe the use of Continuity Check Messages (CCMs) that may be periodically transmitted by a network node throughout the network, thereby informing other nodes of its status. The standards describe similar mechanisms for verifying the location of a fault in the network.
Network operators typically configure the CFM mechanisms described in these standards such that the nodes exchange multicast messages. Thus, when a node sends a CFM message, it is typically received by multiple nodes. In some circumstances, however, it may be desirable to send a message containing information specific to a single node, rather than a group of nodes. In these instances, multicast messaging is insufficient and point-to-point unicast functionality is necessary.
Unfortunately, configuring the CFM mechanisms of Y.1731 and 802.1ag for point-to-point functionality is complex, time-consuming, and inefficient. In particular, when point-to-point functionality is required, a network operator must establish a separate maintenance association for each connection. Furthermore, the network operator must also establish a local maintenance endpoint within every maintenance association. In addition to making configuration a time-consuming, burdensome task, this configuration also requires a large amount of storage, as the network node must maintain data regarding each maintenance association and endpoint.
For the foregoing reasons and for further reasons that will be apparent to those of skill in the art upon reading and understanding this specification, there is a need for simplified configuration of point-to-point connectivity fault management in Ethernet networks.